International Conference on Rheology and Fluid Mechanics November 10-11, 2016 Alicante, Spain

The use of various fillers incorporated into the polymers has gained popularity as it comes as a means of reducing costs and bestows certain worthwhile properties to the polymer. These properties include mechanical, thermal, electrical and magnetic properties. The rheological properties of filled polymers are determined by:-

• The type of filler
• Size of filler
• Shape of filler
• Size distribution
• And amount of filler incorporated

Enthalpic interactions modify the entropic statistical behaviour of an ideal polymer chain. This means that there are no net expansive forces, in other words it does not matter whether monomers in contact are part of the same chain or on different chains. Result is that the scaling exponent for an ideal random walk (ν = 0.5) is recovered. Polymer experiences a very strong attractive potential This could be either a low temperatures (we have previously ignored attractive part of vdW force) or when polymer is placed in very poor solvent This globular state is very important in biopolymers (proteins, DNA) and is also significant in synthetic polymer processing.

We can tell that the fluid behaviour is non-Newtonian if the simple shear data doesn’t pass through the origin and/or doesn’t result in a linearity of graph between the shear stress and shear rate . Non-Newtonian fluids change their viscosity as well as flow behaviour under the action of stress. Application of force to such fluids makes them thicker and acts like a solid, whereas in some cases it may result in the opposite behaviour i.e. they may get runnier than they were before. Removing the stress will make them return to their earlier state.

The materials that show both viscous as well as elastic properties while undergoing deformation are categorised as Viscoelastic and the properties of the same are called viscoelasticity.  Viscoelasticity can be in general terms called as a molecular rearrangement. When stress is applied to such a material, say a polymer, parts of the long polymer chain tends to change position. This rearrangement or change is called creep.

Interfacial rheology is a special branch of rheology that involves studying the unique two-dimensional systems formed at interfaces. Just as rheology is the study of flow in bulk fluids, interfacial rheology is the study of the flow properties of liquid interfaces. These flow properties are important in determining, for example, the behavior and stability of suspensions, emulsions, froth and foams.Emulsion and foam stability, bubble and micelle formation, breakage and fusion and interfacial reactions are largely affected by the rheological properties of the interface. For industries utilizing emulsions and dispersions, such as coatings, food, oil and chemical industries, interfacial rheology can be key when developing and improving processes and products. Most biochemical reactions in nature occur at or in interfaces, such as cell walls and other membranes, and understanding the rheology is one factor in understanding and mimicking the biological system.

Computational rheology involves the design, implementation, and use of numerical methods for the computer simulation of the flow of non-Newtonian fluids in complex geometries. Polymer solutions and melts, like other rheologicallycomplex fluids, exhibit a variety of non-Newtonian flow properties. The viscoelastic character of a given flow is often measured by the dimensionless Weissenberg number We, defined as the product of a characteristic relaxation time of the fluid and a characteristic deformation rate of the flow.

Self-assembly as a course to materials have its foundations firmly in organic chemistry. Self-assembly, hence, embraces all scales, with the possible possibilities of a completely rational and predictable path to materials. The forces that accounts for materials self-assembly at length scales except the molecular force include capillary, colloidal, elastic, electric, and magnetic and shear. The system advances towards a position of lower free energy and greater structural stability.

Microfluidics is the science as well as technology of systems that deals with the processing and manipulation of small amount of fluids, generally 10^-9 to 10­^-18 litres, using directions with dimensions varying between tens and hundreds of micrometres. Microfluidics promises to offer fundamentally new capabilities in controlling the concentrations of molecules in space and time.

Large molecules that are formed by joining smaller sub units called Monomers are termed as Biological macro molecules and are important to living organisms. The macro molecules are broadly divided into the following categories.

• Carbohydrates
• Lipids
• Proteins
• Nucleic acids

• Biological macromolecules are important cellular components and perform a wide array of functions necessary for the survival and growth of living organisms,
• Biological macromolecules are polymers that are synthesized via dehydration reactions among smaller components called monomers.
• Biological macromolecules can be broken back down into their simpler components via hydrolysis reactions.
• The four major classes of biological macromolecules are carbohydrates, lipids, proteins, and nucleic acids.

Food Rheology is simply the study of rheological properties of food which includes the consistency and flow of food under tightly specified conditions. Food is classified into various categories like solid, gel, liquid, emulsion according to its rheological properties. These properties hence affect the food processing plants ‘design which in turn makes food rheology a very important field of study.

The aim of Bio rheology is to determine the dynamics of physiological processes at all levels and characterize them. It also provides explanations to the relationships between rheological properties of various biological systems. These studies includes both animal and plant systems. They  can be divided  in broad contexts like the rheology of macromolecules as well as macromolecular arrays  and also  in narrower contexts like the rheology in cells, tissues or organs.

Microrheology is a technique used to measure the rheological properties of a medium, such as microviscosity, via the measurement of the trajectory of a flow tracer (a micrometre-sized particle). It is a new way of doing rheology, traditionally done using a rheometer.

Micro rheology effectively measures material properties on the scale of the probe used i.e. the colloidal tracer particles present in the sample. These techniques are called micro rheology as they can locally measure the viscoelastic parameters. The popular principle behind micro rheology is to reduce the mechanical probe that is deforming the medium. Modern high-resolution microscopy and the application of micrometre sized spheres as probes, in synchronicity, has allowed the measurement of rheological material properties at the micrometre scale.

Concrete rheology is most important to decide the workability of the concrete and mortar. Here the rheological properties of the fresh cement paste are the key parameter .Adding less water increases the mechanical properties of the hardened concrete. However reducing the water-to-cement ratio may decrease the ease of mixing as well as its application. To avoid these unwanted effects, super-plasticizers are added to decrease the yield stress and the viscosity of the fresh paste. Addition  of plasticizer highly improves concrete and mortar properties.

Rheology play an important role in the petroleum industry, in drilling as well as the production. Petroleum products are not simple mixtures. They are complex mixtures of hydrocarbon compounds. They consists of simplest of gases like methane to large asphaltenic molecules with molecular weights of thousands. This chemical variation results in variations of viscosities and rheological properties.

The various fields of pharmaceuticals where rheological studies are considered are gels like creams and precursors, emulsions and aerosols. It may so happen that it has effects on patients’ acceptability of the product, physical stability, biological availability, etc.

Compressible flow deals with flows having remarkable changes in fluid density. Gases, display such behavior. The Mach number must be greater than about 0.3 (since the density change is greater than 5% in that case), to differentiate compressible from in-compressible flow in air, . The study of compressible flow is pertinent to high-speed aircraft, jet engines, rocket motors, hyper-loops, high-speed entry into a planetary atmosphere, gas pipelines, commercial applications such as abrasive blasting, and many other fields.

Turbulence or turbulent flow is a flow regime characterized by chaotic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and flow velocity in space and time.

In numerous fields of study, the component of instability within a system is generally characterized by some of the outputs or internal states growing without bounds. Not all systems that are not stable are unstable; systems can also be marginally stable or exhibit limit cycle behavior

The fundamental basis of almost all CFD problems are the Navier–Stokes equations, which define many single-phase (gas or liquid, but not both) fluid flows. These equations can be simplified by removing terms describing viscous actions to yield the Euler equations. Further simplification, by removing terms describing vorticity yields the full potential equations. Finally, for small perturbations in subsonic and supersonic flows (not transonic or hypersonic) these equations can be linearized to yield the linearized potential equations.

The fluid flow control systems can be classified depending on the type of pressure source,on the pipe system structure and on the control element. Depending on the pressure sourcetype, the flow control systems can be equipped with centrifugal pumps or volumetricpumps. Concerning the pipe structure, the flow control systems can be used within thehydraulic systems with branches or without branches. The control element within the flowcontrol systems can be the control valve or theassembly variable frequency drive – electricengine - centrifugal pumps.

Accurate prediction of highly vortical flows in a transonic environment has been along-standing dilemma in computational fluid dynamics because the artificial dissipa-tion required inevitably for shock capturing significantlyaffects the evolution of vortices.Typical examples include shock–turbulence interactionsand helicopterrotor flows. Even though this predicament is most commonly found incompressible-flow simulations, many incompressible CFD codes based on upwind dis-cretizations for stability and robustness at high Reynoldsnumbers are also confrontedwith the same problem.

Geophysical fluid dynamics is the study of naturally occurring, large-scale flows on Earth and other planets. It is applied to the motion of fluids in the ocean and outer core, and to gases in the atmosphere of Earth and other planets.

Bio-fluid mechanics is the study of a certain class of biological problems from a fluid mechanics point of view. Biofluid mechanics does not involve any new development of the general principles of fluid mechanics but it does involve some new applications of the method of fluid mechanics. Complex movements of fluids in the biological system demand for their analysis professional fluid mechanics skills.

Magneto-hydrodynamic (MHD) (magneto fluid dynamics or hydromagnetics) is the study of the magnetic properties of electrically conducting fluids. Examples of such magneto-fluids include plasmas, liquid metals, and salt water or electrolytes.

In fluid mechanics, multiphase flow is simultaneous flow of (a) materials with different states or phases (i.e. gas, liquid or solid), or (b) materials with different chemical properties but in the same state or phase (i.e. liquid-liquid systems such as oil droplets in water).

he relatively recent increase in computational power available for mathematical modeling and simulation raises the possibility that modern numerical methods can play a significant role in the analysis of complex particulate flows.

The Environmental Fluid Dynamics studies flow and transport in a diverse range of environmental systems, including the atmosphere, the oceans, lakes, streams and subsurface environments (e.g. groundwater, oil) as well as the interfaces that connect these diverse systems.